For the past few weeks I've been working daily on proximity "training" with Cotton - mostly using negative reinforcement to move away a step when he relaxes his stance after I move toward him.
The last couple of days I've done the same but added clicker. And yesterday/today added giving bits of walnut in his treat bowl after clicking (so, click, pause a half second, then move forward to drop walnut at which point he moves away, I look away and wait for him to come back then start again).
Just now he let me get about 15 inches from the cage door and I was able to drop the walnut directly into the bowl instead of having to move past his comfort zone. This is the closest I've gotten since going to the vet so that's exciting.
He has always been very clear where his threshold is and that he is going to move this forward SLOWLY. In the last week however he's started only taking one step away then checking to see if I'm paying attention instead of looking at me like I'm not getting it and going several feet away. So fingers crossed I'm getting better at reading his body language.
I think that he's super smart and he definitely notices all the little missteps I make. When I set up foraging puzzles he looks like he's barely paying attention but then goes straight to them to check them out. Any changes in his environment he explores right away. So he's way ahead of me on any training session I attempt lol
He's figured out which sounds will make the dog leave the room when she's barking